The present invention is related to bulk material supporting apparatus.
Conventional bulk material beds on vehicles such as trucks or trailers have very heavy frameworks to assure that the beds will not fatigue and collapse under loaded conditions. Since the framework adds to the total weight of the bed as a unit, it is desirable to keep the amount and size of frame components utilized to a minimum in order to provide a lightweight bed providing the bulk carrying capacity needed. Excessive framework adds substantially to the total weight of the bed and therefore decreases its hauling capacity due to weight limitations encountered under regulations limiting usage of such equipment. The weight of such framework also reduces fuel economy of towing vehicles whether the bed is loaded or unloaded.
Previous bulk material carriers have been designed with a network of external frame members arranged in a truss-like fashion. However, the frame members have always been an integral part of the bulk material bed and are therefore confined or restricted to the physical dimensions of the bed. Such beds are often relatively shallow and substantially elongated. By confining the support framework to engagement with the bed, a certain amount of longitudinal rigidity is sacrificed. This is made up for by adding frame members, thereby increasing the unit weight of the carrier.
It therefore becomes desirable to obtain some form of bulk material carrier that is lightweight in construction and yet provides load carrying capacities similar to that of conventional carriers. It is also desirable to provide a bulk material carrier with an external skeletal framework that will provide longitudinal rigidity to the bulk material bed.